The present invention relates to a semiconductor IC device in which an LOC (Lead On Chip) type lead frame bonded to a semiconductor pellet is electrically connected to the semiconductor pellet through bonding wires.
FIGS. 3A and 3B show a semiconductor IC device including a conventional LOC type lead frame.
The conventional LOC type lead frame includes leads 17 and connecting terminals 16 constituted by conductive plates and connected to the leads 17. An insulating film 14 is formed on portions of a semiconductor pellet 11 which correspond to the connecting terminals 16.
The LOC type lead frame is fixed on the major surface of the semiconductor pellet 11, on which active elements and the like are formed, by an adhesive agent or the like. Electrodes 29 formed on a peripheral portion of the major surface of the semiconductor pellet 11 are electrically connected to the connecting terminals 16 through bonding wires 25.
The semiconductor IC device including the conventional LOC type lead frame, however, has the following drawback. Since the connecting terminals 16 are arranged on the major surface of the semiconductor pellet 11, on which the active elements are formed, through the insulating film 14, the connecting terminals 16 are located close to the internal circuit formed in the semiconductor pellet 11. For this reason, if a vertical electric field is generated by the connecting terminals 16 due to voltages, such as input/output signals, externally applied to the leads 17, this electric field enters the internal circuit of the semiconductor pellet 11. Since the active elements formed on the semiconductor pellet 11 are operated by signals of low potentials, various kinds of inconvenience may be caused, e.g., the internal circuit of the semiconductor pellet 11 is influenced by the electric field, and the operation margin of the semiconductor IC device is reduced.